Silencerco 1/2x28 ASR Flash Hider - 9mm Luger - The ASR Flash Hider is compatible with Silencerco ASR (Active Spring Retention) Mounts. The ASR Mount is a quick attach/detach system for almost all Silencerco suppressors. The simple one-hand-on, one-hand-off mounting system is compatible with all ASR Muzzle Devices to promote ease of transfer from one silencer to another. Once shouldered, the locking ring ensures the silencer won't rotate or work itself loose under a heavy firing schedule. The patent-pending resonance suppression effectively eliminates the tuning-fork effect common with competing 3-prong Flash Hiders.